Effectiveness of Calcitonin Gene-Related Peptide Monoclonal Antibodies in the Prevention of Migraine: A Systematic Review and Meta-Analysis of Observational Cohort Studies

Background and Objective Migraine is a neurological disorder characterized by episodes of moderate-to-severe headache. The emergence of drugs derived from monoclonal antibodies specific for the calcitonin gene has brought forth a therapeutic option for patients in whom the traditional treatments have failed. This study aimed to evaluate the clinical effectiveness of calcitonin gene-related peptide antibodies in the prevention of migraine through a systematic review and meta-analysis of observational cohort studies. Methods A literature search for evidence was performed in electronic databases for observational studies that evaluated adult patients with migraine receiving calcitonin gene-related peptide receptor antagonists (e.g. erenumab, fremanezumab, galcanezumab and eptinezumab) and reported effectiveness outcomes (mean reduction in monthly migraine/headache days, and proportion of patients with 50% or greater reduction in migraine/headache days). Results During the screening process, 47 records were included for data extraction and qualitative and quantitative analyses. The overall rate of patients with a reduction of at least 50% of mean monthly migraine days was 54% (95% CI 49–59%), and overall mean monthly migraine reduction was about 7.7 days (95% CI 8.4–7.0 days). Regarding the outcome ≥ 50% reduction in mean monthly headache reduction, the overall rate of patients with a reduction of at least 50% was 57% (95% CI 48–64%), and the overall mean monthly headache reduction was approximately 8.8 days (95% CI 10.1–7.5 days). Subgroup analyses considering the drug treatment used and type of migraine were consistent with previous results. Conclusions The use of calcitonin gene-related peptide antibodies in real-world studies to prevent migraine demonstrates promising effectiveness outcomes, in agreement with those reported in previously published randomized clinical trial reports.